某电路接入一只阻值为15Ω的电阻R1,其中的电流为0.6A。如果设电路再并联一个

题型:填空题

问题:

某电路接入一只阻值为15Ω的电阻R1,其中的电流为0.6A。如果设电路再并联一个阻值为30Ω的电阻R2,电路的总电流变化了________A,R2的电功率为___________。

考点:电功率的计算欧姆定律及其应用并联电路的电流规律
题型:填空题

(7分)下图是实验室常用的实验装置图,试回答下列问题:

(1)装置B中仪器a的名称为:   ▲   

(2)实验室用A装置制取氧气的化学方程式为:   ▲   ,某学生用C装置收集O2,当   ▲   时,说明O2已经收满。

(3)用B装置制取CO2气体时,需先将石灰石放入   ▲   (填仪器名称)中,若要用排空气法收集CO2气体,应该选用   ▲   (填序号)装置收集。

(4)已知:常温下,硫化氢(H2S)是一种有臭鸡蛋气味的气体,密度比空气大,实验室可以用硫化亚铁(FeS)固体和稀硫酸反应而制得,其反应的化学方程式为:FeS+H2SO4=H2S↑+FeSO4,则实验室制取H2S应选择   ▲   (填序号)作为气体发生装置。

题型:填空题

电视演播室是利用光和声进行空间艺术创作的场所,大型演播室一般是在()。

A.400m2以上

B.500m2以上

C.600m2以上

D.800m2以上

题型:填空题

But let no one think that pleasure is immoral. Pleasure in itself is a great good, all pleasure, but its consequences may be such (31) the sensible person eschews certain varieties of (32) Nor need pleasure be gross and sensual. They are wise in their generation (33) have discovered that intellectual pleasure is the most satisfying and the most enduring. It is well to (34) the habit of reading. There are (35) sports in which you can engage to your own satisfaction after you have passed the prime of life; there are no games except patience, chess problems and crossword puzzles that you can play without someone to play them with you. Reading suffers (36) no such disadvantages; there is no occupation—except perhaps needle- work, but that leaves the restless spirit (37) liberty—which you can more easily (38) up at any moment, for any period, and more easily put (39) when other calls press upon you; there is no other amusement that can be obtained in these happy days of public liberties and cheap editions at so small a (40) . To acquire the habit of reading is to construct for yourself a refuge from almost all the miseries of life.

A.his

B.its

C.it

D.him

题型:填空题

治疗心、胸、胃疾病宜选用哪组配穴( )

A.内关、公孙

B.照海、列缺

C.后溪、申脉

D.中脘、足三里

E.外关、足临泣

题型:填空题

车辆管理所应当在申请人参加领证宣誓仪式的一日内核发机动车驾驶证。

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